Dr. Khalid A. Syed
Arthritis means loss of cartilage. Cartilage is the gliding surface that coats the ends of bones inside our joints such (as the knee). Cartilage is unique in that it does not heal, repair or regenerate. What you have at puberty is what you get. The body never makes more. The only thing that can happen to the cartilage is that it can be worn out and lost. That is what we call Osteoarthritis.
There are many reasons for loss of cartilage. The most common cause is wear and tear that happens with time, use, life, work etc. Another cause is trauma and injuries such as fractures, ligament tears etc. Another way to get arthritis are inflammatory conditions such as lupus, rheumatoid arthritis, psoriasis where the body's own immune system destroys the cartilage.
The final result of all of these is damaged cartilage which does not have the potential to regenerate. The body does have a limited capacity to generate scar tissue to fill holes in cartilage but this tissue is not durable like cartilage is and does not last.
As more and more cartilage is worn out the bones become exposed. Exposed bone is like stone, rough and abrasive. This causes inflammation which in turn results in pain and swelling in the joint. With time, this gets worse and worse until the pain becomes debilitating and affects function.
Arthritis is a common condition and the number of people with arthritis (Burden of Disease) is very large. It leads to great suffering and disability. It leads to loss of work time, increase in pain medication use and loss of mobility and independence.
Treating arthritis is multimodal and stepwise.
In its early stages, arthritis is treated with life style changes. Weight loss and exercise are useful tools. Weight loss leads to less load on joints and hence less wear and inflammation. Exercise leads to strengthening of the muscles around the joint and hence, less of the load goes through the joint surface hence, less pain and inflammation. There is increasing scientific evidence that high caloric diets and high fat diets lead to metabolic changes in the weight bearing joints such as knees. These metabolic changes persist even if the excess weight is lost and lead to earlier degeneration of cartilage.
In terms of medications, tylenol or acetaminophen is considered the frontline medication. However, based on scientific literature, there is limited benefit in terms of pain control and potential liver toxicity .
Anti-inflammatory medications such as ibuprofen, naproxen, diclofenac and others are options to help with pain and inflammations. Anti-inflammatory medications have been shown to help with pain and function but they have to be taken for a period of time like 6 to 12 weeks regularly to work as anti-inflammatories. Also, they have side effects in terms of stomach upset, high blood pressure and damage to kidneys and patients on them need to be monitored for these. In certain cases, they can cause stomach ulcers and life threatening bleeding.
Patients also take supplements such as glucosamine but the science on these is not conclusive. They do not regenerate cartilage. Some studies have shown that they help pain symptoms from arthritis. Other studies show no benefit. If one is to take them, they should be taken for at least 3 to 4 months to notice an effect. The only way to know if they will work for you, is to take them and see if there is a benefit.
Then there are injections. The first line joint injection is cortisone. The kind of cortisone that is used for joint injection is synthesized with an attached very large molecule that cannot be absorbed in the body. Hence, the cortisone does not circulate in the bloodstream and patients don't get a systemic effect. Cortisone is an anti-inflammatory and calms the inflammation in the joint and hence pain. It is effective for 3-6 months and can be repeated 3 to 4times per year if necessary.
Another option for injections is hyalouronic acid injections. These injections attempt to simulate the body's natural joint fluid. They function as lubricants and coat the joint surface. They also have an anti-inflammatory effect. There is evidence that high molecular weight products work better than low molecular brands. The relief lasts from 6 mo to a year or two. They can be repeatedly as necessary.
Platelet Rich Plasma (PRP) is a newer technology that has been around for about 4 years. It involves isolating the plasma from a person's blood. This layer has platelets, hormones and circulating stem cells. PRP treatments involve three injections 1 week apart. Effect can take upto 3 months to show and can last for upto 2 years. A large meta-analysis showed pain relief for knee arthritis in 2013. It is also used for ankle OA and shoulder problems. At this stage, it is not clear as to how PRP works. However, the prevailing theory is that it biologically modulates inflammation and helps pain.
The latest option is autologous stem cells. These are stem cells taken from patient's own fat cells or bone marrow and are processed and injected into the joint. Stem cells have the potential to repair cartilage defects. As the patient's own cells are used, there is no risk of rejection. The procedure is done in the clinic under local anesthetic and patients can walk afterwards.
The final option for joint arthritis is joint replacement.